ABSTRACT
Abstract Development of ceftriaxone loaded nanostructured lipid carriers to increase permeability of ceftriaxone across uninflamed meninges after parenteral administration. Lipids were selected by theoretical and experimental techniques and optimization of NLCs done by response surface methodology using Box-Behnken design. The Δδt for glyceryl monostearate and Capryol90 were 4.39 and 2.92 respectively. The drug had maximum solubility of 0.175% (w/w) in glycerol monostearate and 2.56g of Capryol90 dissolved 10mg of drug. The binary mixture consisted of glyceryl monostearate and Capryol90 in a ratio of 70:30. The optimized NLCs particle size was 130.54nm, polydispersity index 0.28, % entrapment efficiency 44.32%, zeta potential -29.05mV, and % drug loading 8.10%. In vitro permeability of ceftriaxone loaded NLCs was 5.06x10-6 cm/s; evidently, the NLCs pervaded through uninflamed meninges, which, was further confirmed from in vivo biodistribution studies. The ratio of drug concentration between brain and plasma for ceftriaxone loaded NLCs was 0.29 and that for ceftriaxone solution was 0.02. With 44.32% entrapment of the drug in NLCs the biodistribution of ceftriaxone was enhanced 7.9 times compared with that of ceftriaxone solution. DSC and XRD studies revealed formation of imperfect crystalline NLCs. NLCs improved permeability of ceftriaxone through uninflamed meninges resulting in better management of CNS infections.
Subject(s)
Ceftriaxone/agonists , Triage/classification , Lipids/analysis , X-Ray Diffraction/instrumentation , In Vitro Techniques/methods , Central Nervous System Infections/pathologyABSTRACT
The macroporous microspheres were prepared through suspension polymerization and based on a copolymer of glycidyl methacrylate and ethylene glycol dimethacrylate.The effect of porogen on the microspheres structure was evaluated in terms of pore size and surface area.Porogen contained dichloromethane (δ=9.7 (cal/cm3)1/2) and N-octanol (δ=10.3 (cal/cm3)1/2) which corresponded to a good and poor solvent,respectively.The solubility parameter of porogen was controlled in the range of 9.89-10.09 (cal/cm3)1/2.The pore size of microspheres increased with the difference value of solubility parameter between the polymer and the porogen.On the contrary,the surface area of microspheres decreased in this study.The anion exchange media was prepared through coupling poly(ethylene imine) in the microspheres,and the proteins transport was determined by frontal analysis method.The macroporous microspheres with 257 nm pore size could still afford a high proteins capacity (45.1 mg/mL).These macroporous supports showed a large potential in a rapid separation of proteins.
ABSTRACT
Extended Hildebrand Solubility Approach (EHSA) was applied to evaluate the solubility of sulfadiazine, sulfamerazine, and sulfamethazine in some ethanol + water mixtures at 298.15 K. Reported experimental equilibrium solubilities and some fusion properties of these drugs were used for the calculations. In particular, a good predictive character of EHSA (with mean deviations lower than 3.0%) were found by using regular polynomials in order four correlating the interaction parameter W with the Hildebrand solubility parameter of solvent mixtures without drug. The predictive character of EHSA was the same as that obtained by direct correlation of drug solubilities with the same descriptor of polarity of the cosolvent mixtures.
Se aplicó el Método Extendido de Solubilidad de Hildebrand (MESH) al estudio de la solubilidad de sulfadiazina, sulfamerazina y sulfametazina en mezclas binarias etanol + agua a 298,15 K. Se utilizaron valores reportados de solubilidad en equilibrio y algunas propiedades fisicoquímicas de fusión de estos compuestos. Se obtuvo una adecuada capacidad predictiva del MESH (con desviaciones promedio menores del 3,0%) al utilizar modelos polinómicos regulares de cuarto orden relacionando el parámetro de interacción W con el parámetro de solubilidad de Hildebrand de las mezclas solventes. El carácter predictivo del MESH fue de magnitud semejante al que se obtuvo calculando esta propiedad directamente, donde se utilizó una regresión empírica regular de cuarto orden de la solubilidad experimental logarítmica de los fármacos en función del parámetro de solubilidad de las mezclas disolventes.
Na presente investigação, aplicou-se o Método Estendido de Solubilidade do Hildebrand (MESH) ao estudo da solubilidade da sulfadiazina, sulfamerazina e sulfametazina em misturas binárias etanol + agua a 298,15 K. Obteve-se uma adequada capacidade preditiva (com menor desvio padrão de 3,0%) do MESH ao utilizar modelos polinomiais regulares de quarta ordem relacionando o parâmetro de interação W com o parâmetro de solubilidade do Hildebrand das misturas de solventes. O caráter preditivo do MESH foi semelhante ao obtido pelo cálculo utilizando uma regressão empírica regular da quarta ordem, da solubilidade experimental logarítmica dos fármacos em função do parâmetro de solubilidade das misturas dissolventes.
ABSTRACT
La nimodipina (NMD) es un agente usado como vasodilatador cerebral y cuyas propiedades fisicoquímicas en solución aún no han sido totalmente estudiadas. En la presente investigación se aplicó el Método Extendido de Solubilidad de Hildebrand (MESH) al estudio de la solubilidad de NMD en algunas mezclas binarias PEG 400 + etanol a 298,15 K. Se obtuvo una capacidad predictiva aceptable del MESH (desviación general inferior al 1,3%) al utilizar un modelo polinómico regular de tercer orden, relacionando el parámetro de interacción W con el parámetro de solubilidad de las mezclas solventes. De esta forma, las desviaciones obtenidas en la solubilidad estimada fueron de magnitud inferior a las obtenidas al calcular esta propiedad directamente, utilizando una regresión empírica regular del mismo orden, de la solubilidad experimental del fármaco en función del parámetro de solubilidad de las mezclas disolventes, en la cual se obtuvo una desviación promedio del 1,7%.
Nimodipine (NMD) is a drug used as cerebral vasodilator whose physicochemical properties in solution have not been studied completely. In this work the Extended Hildebrand Solubility Approach (EHSA) was applied to evaluate the equilibrium solubility of NMD in some polyethylene glycol 400 + ethanol mixtures at 298.15 K. An acceptable correlative capacity of EHSA was found using a regular polynomial model in order three (overall deviation lower than 1.3%), when the W interaction parameter is related to the solubility parameter of the mixtures. Moreover, the mean deviation obtained in the estimated solubility with respect to experimental solubility was lower than the one obtained directly by means of an empiric regression in order three of the logarithm experimental solubility as a function of the mixtures' solubility parameters (1.7%).
ABSTRACT
The Extended Hildebrand Solubility Approach(EHSA) was applied in the present work to evaluate the solubility of the analgesic drug acetaminophen (paracetamol) in polyethylene glycol 400 + water mixtures at 298.15 K. An acceptable correlative capacity of EHSA was found using a regular polynomial model in order four (overall deviation below 0.7%), when the W interaction parameter is related to the solubility parameter of the mixtures. Thus, the deviations obtained in the estimated solubility with respect to experimental solubility were lower than those obtained directly by means of an empiric regression of the experimental solubility as a function of the mixtures´ solubility parameters (close to 1.5%).
En el presente trabajo se aplicó el Método Extendido de Solubilidad de Hildebrand (MESH) al estudio de la solubilidad del acetaminofeno en mezclas binarias polietilenglicol 400 + agua a 298,15 K. Se obtuvo una capacidad predictiva aceptable del MESH (desviación general inferior al 0,7%) al utilizar un modelo polinómico regular de cuarto orden que relaciona el parámetro de interacción W con el parámetro de solubilidad de las mezclas solventes. Las desviaciones obtenidas en la solubilidad estimada fueron de menor magnitud que las obtenidas al calcular esta propiedad directamente, utilizando una regresión empírica regular del mismo orden de la solubilidad experimental del fármaco en función del parámetro de solubilidad de las mezclas disolventes (cerca del 1.5%).
O método estendido de solubilidade de Hildebrand (MESH) foi aplicado nesta pesquisa para avaliar a solubilidade do paracetamol em água de misturas binárias + polietileno glicol 400 em 298,15 K. Obteve-se boa capacidade preditiva com o MESH (desvio inferior a 0,7%) quando se utiliza um polinòmio regular de quarta ordem do parâmetro de interação W com o parâmetro de solubilidade das misturas de solventes. Os desvios obtidos na solubilidade estimada foram inferiores do que os obtidos através do cálculo desta propriedade diretamente, utilizando uma regressão normal empírica da mesma ordem da solubilidade experimental da droga em função do parâmetro de solubilidade das misturas solventes (cerca de 1,5 %).
ABSTRACT
OBJECTIVE: To investigate the properties of polyacrylic: resin Eudragit L100-Eudragit S100 (mixed at ratio of 1:4) free film and its various influencing factors. METHODS: The free film was prepared by casting method,and its solubility parameter, intrinsic viscosity, tensile strength and permeability were determined. The optimal solvent and plaslicizer were screened. RESULTS: The tensile strength of the film prepared by ethanol was maximum, and the permeability of the free film made using acetone was the highest, therefore ethanol was the optimal solvent. Plasticizer could decrease the tensile strength and increase the permeability of free film,and diethyl phthalate was the optimal plasticizer. CONCLUSION: The present investigation might be helpful for screening coating formulation and optimizing coating process.
ABSTRACT
OBJECTIVES: This study investigated the effect of the strength and wetting characteristics of adhesives on the bond strength to dentin. The experimental adhesives containing various ratios of hydrophobic, low-viscosity Bis-M-GMA, with Bis-GMA and TEGDMA, were made and evaluated on the mechanical properties and bond strength to dentin. MATERIALS AND METHODS: Five experimental adhesives formulated with various Bis-GMA/Bis-M-GMA/TEGDMA ratios were evaluated on their viscosity, degree of conversion (DC), flexural strength (FS), and microtensile bond strength (MTBS). The bonded interfaces were evaluated with SEM and the solubility parameter was calculated to understand the wetting characteristics of the adhesives. RESULTS: Although there were no significant differences in the DC between the experimental adhesives at 48 hr after curing (p > 0.05), the experimental adhesives that did not contain Bis-GMA exhibited a lower FS than did those containing Bis-GMA (p < 0.05). The experimental adhesives that had very little to no TEGDMA showed significantly lower MTBS than did those containing a higher content of TEGDMA (p < 0.05). The formers exhibited gaps at the interface between the adhesive layer and the hybrid layer. The solubility parameter of TEGDMA approximated those of the components of the primed dentin, rather than Bis-GMA and Bis-M-GMA. CONCLUSIONS: To achieve a good dentin bond, a strong base monomer, such as Bis-GMA, cannot be completely replaced by Bis-M-GMA for maintaining mechanical strength. For compatible copolymerization between the adhesive and the primed dentin as well as dense cross-linking of the adhesive layer, at least 30% fraction of TEGDMA is also needed.
Subject(s)
Adhesives , Benzhydryl Compounds , Bisphenol A-Glycidyl Methacrylate , Chimera , Dentin , Methacrylates , Polyethylene Glycols , Polymethacrylic Acids , Solubility , ViscosityABSTRACT
Indomethacin (IMC) is an analgesic drug whose physicochemical properties have not been thoroughly studied. In this work the Extended Hildebrand Solubility Approach (EHSA) was applied to evaluate the solubility of IMC in ethanol + water mixtures at 298.15 K. An acceptable correlative capacity of EHSA was found using a regular polynomial model in order four (overall deviation lower than 4.1%), when the W interaction parameter is related to the solubility parameter of the mixtures. Besides, the deviations obtained in the estimated solubility with respect to experimental solubility were lower compared with those obtained directly by means of an empiric regression of the experimental solubility as a function of the mixtures solubility parameters.
La indometacina (IMC) es un analgésico cuyas propiedades fisicoquímicas aún no han sido totalmente estudiadas. En la presente investigación, se aplicó el Método Extendido de Solubilidad de Hildebrand (MESH) al estudio de la solubilidad de la IMC en mezclas binarias etanol + agua a 298,15 K. Se obtuvo una capacidad predictiva aceptable del MESH (desviación general inferior al 4,1%) al utilizar un modelo polinómico regular de cuarto orden relacionando el parámetro de interacción W con el parámetro de solubilidad de las mezclas solventes. De esta forma, las desviaciones obtenidas en la solubilidad estimada, fueron de magnitud inferior a las obtenidas al calcular esta propiedad directamente, utilizando una regresión empírica regular del mismo orden, de la solubilidad experimental del fármaco en función del parámetro de solubilidad de las mezclas disolventes.
Subject(s)
Indomethacin , SolubilityABSTRACT
En este trabajo se estudió la solubilidad del Eudragit S100® respecto al pH en medios acuosos y a la polaridad en solventes orgánicos. Además, se estimó el parámetro de solubilidad del polímero [1], de forma experimental y teórica, mediante los métodos de contribución de grupos de Fedors y de van Krevelen, estableciendo su mapa de solubilidad. Los resultados mostraron que la solubilidad del polímero depende del pH siendo soluble a partir de pH 6,0. El valor [1] estimado experimentalmente fue de 12,9 [1] 2,4 cal1/2 cm-3/2 siendo casi concordante con los obtenidos mediante los métodos de Fedors y de van Krevelen. Adicionalmente, se construyó el diagrama de Teas para la identificación de solventes y no solventes para el polímero.
In this paper the solubility of Eudragit S100® was studied with respect to pH in aqueous media and with respect to the polarity of some organic solvents. The polymer solubility parameter [1], was established by means of experimental solubility determinations and by theoretical ways, by using the Fedors and van Krevelen methods, which are based on groups’ contribution. The respective solubility map was thus established. The results show that the polymer is soluble in water over pH 6.0. The [1] value obtained experimentally was 12.9 [1] 2.4 cal1/2 cm-3/2, which is almost concordant with those obtained by means of Fedors and van Krevelen’s methods. In turn, the Teas diagram was developed for identifying the solvents and non-solvents for this polymer.
Neste papel o solubilidade de Eudragit S100® foi estudado com respeito ao pH em meios aqueus e com respeito à polaridade de alguns solventes orgânicos. O parâmetro da solubilidade ( ) do polímero foi estabelecido por meio das determinações experimentais da solubilidade e por maneiras teóricas, usando os métodos de Fedors e de van Krevelen, que são baseados na contribuição dos grupos funcionais. O mapa respectivo da solubilidade foi estabelecido assim. Os resultados mostram que o polímero é solúvel na água a pH maior que 6,0. O valor obtido experimentalmente foram 12,9 [1] 2,4 cal1/2 cm-3/2, que é quase concordante com os aqueles obtidos por meio de métodos de Fedors e de van Krevelen. Por sua vez, o diagrama dos Teas foi desenvolvido identificando os solventes e os não solventes para este polímero.